Surface morphology of Ag(110) close to its roughening transition

Abstract

We have investigated the thermal roughening of the Ag(110) surface using synchrotron x-ray diffraction. The data taken out of plane (nonzero perpendicular momentum transfer) show a clear two-component line shape below the roughening transition at ${\mathit{T}}_{\mathit{R}}$=790 K. We interpret this as coexistence of flat (110)-oriented regions and slightly inclined, rough regions on the surface below ${\mathit{T}}_{\mathit{R}}$. The temperature dependence of the angle between the components and their relative amplitudes implies that roughening takes place by the gradual replacement of the (110) faceted regions by the rough phase.